TWZRD Receipt Verifier (standalone)

Verify a TWZRD receipt offline, trusting nothing from TWZRD's servers or codebase - only the receipt, TWZRD's published public key, and two widely-audited crypto libraries. The verifier auto-detects two receipt families:

For V5/V6 the verifier reads the domain the receipt carries and applies the matching leaf rules (V6 binds the reputation_* provenance fields into the signed leaf; V5 left them unsigned). For cNFT receipts there is no leaf - tamper-evidence is the signature: any change to a signed field (including the wallet) invalidates it.

If it says VALID, the receipt was authored by TWZRD and was not altered. Unsigned, wrong-key, wrong-wallet, or tampered receipts fail.

Where this fits: the agent trust loop

This verifier is the last step of the x402 trust rail an agent runs before and after it spends:

1. Discover a model/provider - wzrd-client (PyPI) or @wzrd_sol/sdk (npm)
2. Preflight the seller wallet, free - POST https://intel.twzrd.xyz/v1/intel/preflight (or MCP get_readiness_card_tool)
3. Pay with a signed receipt - GET https://intel.twzrd.xyz/v1/intel/trust/{seller} (0.05 USDC, x402)
4. Verify the receipt offline - this package (trust nothing but the bytes + the public key)

# zero-install: verify a receipt straight from the published package
npx twzrd-receipt-verifier receipt.json --pubkey 9V6Pn19kiUA5Rn6JpQfNduanvGt2aXGwsarosNfa2Ldf

# replay-resistance (opt-in): reject receipts older than 60s — and reject any with no timestamp
npx twzrd-receipt-verifier receipt.json --pubkey 9V6Pn19kiUA5Rn6JpQfNduanvGt2aXGwsarosNfa2Ldf --max-age 60

The published signing key

Also published, machine-readable, at:

• https://intel.twzrd.xyz/.well-known/x402 → receipt.signature.public_key
• https://intel.twzrd.xyz/openapi.json → x402.receipt.signature.public_key
• the MCP card agent-intel-mcp-card.json → receipt_signing.public_key

Most paranoid mode: pin the key out-of-band with --pubkey instead of fetching it, so you never trust the live endpoint to tell you which key to trust.

cNFT Receipts (the 95k genesis receipts)

Every genesis receipt is a compressed NFT on Solana mainnet (tree 8QFdTqBkSeyuvp47dXdpwfWzXTuYSbAC64oT4soPGnXS, verified creator 2ELSDx...). Its at-mint snapshot is published as a signed anchor block in the cNFT metadata, served at https://twzrd.xyz/r/<wallet>.json:

{
  "anchor": {
    "tier_at_mint": "Platinum",
    "score_at_mint": 255,
    "verified_tx": "<solana settlement signature>",
    "behavior_proof": "<sha256 hex>",
    "minted_at": 1782415336,
    "signature": "<128-hex Ed25519 sig>",
    "verify_pubkey": "2ELSDxLkb7dYrN6EUG69tNtULAq4Fo7WPvXyrZPmuFif"
  },
  "live": { "...": "current decayed reputation (NOT signed)" }
}

The signed payload is the compact JSON {wallet, tier_at_mint, score_at_mint, verified_tx, behavior_proof, minted_at} (exact key order). The wallet is the first signed field but is not stored in the anchor - it is the <wallet>.json filename / the cNFT leaf owner - so pass --wallet or keep the filename. The signing key (2ELSDx...) is built in to the verifier (pinned in the audited package); override with --pubkey, or fetch the published copy with --fetch-key.

# fetch a receipt and verify it (wallet inferred from the filename, key built-in)
W=zoz7neLHXoaLwNBuckSqNqaMsacpqJsphtFuNNpQyt3
curl -s https://twzrd.xyz/r/$W.json -o $W.json
npx twzrd-receipt-verifier $W.json --self-test

# or pass the wallet explicitly (e.g. when piping from stdin)
npx twzrd-receipt-verifier anchor.json --wallet $W

# fetch the key from the published descriptor instead of the built-in copy
# (cross-check, or pin to whatever the live domain publishes)
npx twzrd-receipt-verifier $W.json --fetch-key

The key is published, machine-readable, at https://api.twzrd.xyz/v1/receipts/pubkey (and https://twzrd.xyz/.well-known/twzrd-receipt-pubkey) with the full signing spec (public_key, signed_fields, scheme, tree). It must equal the built-in key and the on-chain verified creator of every cNFT in the tree - three independent sources.

mode             : cNFT (Bubblegum anchor)
trusted pubkey   : 2ELSDxLkb7dYrN6EUG69tNtULAq4Fo7WPvXyrZPmuFif  [source: built-in genesis authority]
wallet           : zoz7neLHXoaLwNBuckSqNqaMsacpqJsphtFuNNpQyt3  [source: filename]
signature_valid  : true
RESULT           : VALID (TWZRD-authored, untampered)

Only the anchor block is signed. The live block (current decayed reputation) is informational and intentionally NOT covered by the signature. For full on-chain binding, confirm the cNFT exists in the genesis tree with verified creator 2ELSDx via any DAS provider (getAsset / getAssetProof); the signature alone already proves 2ELSDx authorship of the at-mint snapshot.

Get a receipt to verify

Free sample first — the signature is real, so this proves the whole verify path without paying or holding a wallet:

curl -s https://intel.twzrd.xyz/v1/receipts/example -o sample.json
npx twzrd-receipt-verifier@1.2.2 sample.json \
  --pubkey 9V6Pn19kiUA5Rn6JpQfNduanvGt2aXGwsarosNfa2Ldf

Live paid receipt: GET https://intel.twzrd.xyz/v1/intel/trust/{pubkey} (x402, 0.05 USDC on Solana mainnet) with any x402-capable client — the receipt is the twzrd_receipt object in the response. Since 1.2.2 the verifier auto-unwraps twzrd_receipt, so the raw API response verifies as-is.

This package is only the offline verify step of the trust loop. Free preflight, merchant cards, and discovery live on the remote MCP — https://intel.twzrd.xyz/mcp (23 tools, no wallet).

The receipt object looks like:

{
  "version": "v5",
  "leaf": "0x...",
  "preimage": { "domain": "TWZRD:AO_REPUTATION_RECEIPT_V5", "agent_id": "...", "score": 15, "...": "..." },
  "signature": "base58 ed25519 sig",
  "signing_pubkey": "9V6Pn19kiUA5Rn6JpQfNduanvGt2aXGwsarosNfa2Ldf",
  "key_id": "twzrd-receipt-ed25519-v1",
  "signing_alg": "ed25519"
}

Python

pip install twzrd-receipt-verifier   # PyPI; or: pip install pynacl pycryptodome for script-only use

# fetch the published key and verify:
twzrd-verify-receipt receipt.json
# or: python verify_twzrd_receipt.py receipt.json

# pin the key out-of-band (recommended):
python verify_twzrd_receipt.py receipt.json --pubkey 9V6Pn19kiUA5Rn6JpQfNduanvGt2aXGwsarosNfa2Ldf

# also confirm a tampered copy FAILS:
twzrd-verify-receipt receipt.json --self-test

# replay-resistance (opt-in; same semantics as the npm CLI --max-age):
twzrd-verify-receipt receipt.json --max-age 300

# from stdin:
cat receipt.json | twzrd-verify-receipt -

Source: twzrd-sol/twzrd-receipt-verifier

Node

npm install                          # tweetnacl + js-sha3 + bs58

node verify_twzrd_receipt.js receipt.json
node verify_twzrd_receipt.js receipt.json --pubkey 9V6Pn19kiUA5Rn6JpQfNduanvGt2aXGwsarosNfa2Ldf --self-test
cat receipt.json | node verify_twzrd_receipt.js -

Both exit 0 on VALID, 1 on INVALID.

What it checks (and the exact layout)

The keccak256 leaf preimage is a strict little-endian, length-prefixed concat (reproducible in any language):

domain            = "TWZRD:AO_REPUTATION_RECEIPT_V5"   (or ...ATTENTION... for attention receipts)
agent_id          = u16_le(len(utf8)) || utf8 bytes
score             = u16_le
confidence_bps    = u16_le
timestamp_unix    = u64_le
payer             = 32 bytes  (base58-decoded pubkey, or sha256(marker) for synthetic payers)
settlement_anchor = 32 bytes  (last 32 bytes of the utf-8 settlement_tx string, or 32 zero bytes)

leaf      = keccak256(domain || agent_id || score || confidence_bps || timestamp_unix || payer || settlement_anchor)
signature = Ed25519_sign(receipt_signing_key, leaf_bytes)

The verifier:

1. recomputes leaf from the preimage and compares it to receipt.leaf,
2. confirms receipt.signing_pubkey (if present) equals the trusted key,
3. verifies the Ed25519 signature over the 32 leaf bytes against the trusted key.

VALID requires all three. The settlement_tx in the preimage is an on-chain Solana signature you can independently check for ground truth.

Trust assumptions

You trust: the receipt you were given, the published public key (ideally pinned), and the crypto libraries (PyNaCl/libsodium, pycryptodome; tweetnacl, js-sha3). You do not trust TWZRD's API, database, or this repository's other code. Swap the libraries for your own if you prefer - the byte layout above is the whole spec.